• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1494-1500
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• 2012

Fermentation with filamentous fungi in a bioreactor is a complex dynamic process that is affected by flow conditions and the evolution of the rheological properties of the medium. These properties are mainly affected by the biomass concentration and the morphology of the fungus. In this work, the rheological properties of a fermentation with the fungus Beauveria bassiana under different hydrodynamic conditions were studied and the rheological behavior of this broth was simulated through a mixture of carboxymethyl cellulose sodium and cellulose fibers (CMCNa-SF). The bioreactor was a 10 L CSTR tank operated at different stir velocities. Rheological results were similar at 100 and 300 rpm for both systems. However, there was a significant increase in the viscosity accompanied by a change in the consistence index, calculated according to the power law model, for both systems at 800 rpm. The systems exhibited shear-thinning behavior at all stir velocities, which was determined with the power law model. The mixing time was observed to increase as the cellulose content in the system increased and, consequently, the efficiency of mixing diminished. These results are thought to be due to the rheological and morphological similarities of the two fungal systems. These results will help in the optimization of scale-up production of these fungi.

• 한국정보과학회논문지:시스템및이론
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• 제34권3호
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• pp.113-123
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• 2007

본 논문에서는 $GF(2^m)$상의 고속 타원곡선 암호 프로세서를 제안한다. 제안한 암호 프로세서는 타원곡선 정수 곱셈을 위해 Lopez-Dahab Montgomery 알고리즘을 채택하고， $GF(2^m)$상의 산술 연산을 위해 가우시안 정규 기저(Gaussian Normal Basis: GNB)를 이용한다. 본 논문에서 구현한 타원곡선 암호 프로세서는 m=163을 선택하였으며 NIST(National Institute of Standard and Technology)에서 권고하는 5개의 $GF(2^m)$ 필드 크기 중에서 가장 작은 값으로 GNB 타입 4가 존재한다. 제안한 타원곡선 암호 프로세서는 Host Interface, Data Memory, Instruction Memory, Control로 구성되어 있으며 Xilinx XCV2000E FPGA칩을 이용하여 구현한다. FPGA 구현결과 제안된 타원곡선 암호 프로세서는 기존의 연구결과에 비해 속도에서 약 2.6배의 성능 향상을 보이며 훨씬 낮은 하드웨어 복잡도를 가진다.

• Journal of Microbiology and Biotechnology
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• 제27권2호
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• pp.234-241
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• 2017

Potato peels (PP) contain several bioactive compounds. These compounds are known to provide human health benefits, including antioxidant and antimicrobial properties. In addition, these compounds could have effects on human enteric viruses that have not yet been reported. The objective of the present study was to evaluate the phenolic composition, antioxidant properties in the acidified ethanol extract (AEE) and water extract of PP, and the antiviral effects on the inhibition of Av-05 and MS2 bacteriophages, which were used as human enteric viral surrogates. The AEE showed the highest phenolic content and antioxidant activity. Chlorogenic and caffeic acids were the major phenolic acids. In vitro analysis indicated that PP had a strong antioxidant activity. A 3 h incubation with AEE at a concentration of 5 mg/ml was needed to reduce the PFU/ml (plaque-forming unit per unit volume) of Av-05 and MS2 by 2.8 and $3.9log_{10}$, respectively, in a dose-dependent manner. Our data suggest that PP has potential to be a source of natural antioxidants against enteric viruses.

• 한국컴퓨터정보학회논문지
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• 제17권6호
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• pp.153-161
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• 2012

본 연구는 웹 환경에서 어플리케이션 복잡도의 빈도분포를 근거로 한계값의 적정성을 분석하기 위한 실험을 하였으며 두 가지 가정을 기준으로 작업하였다. 즉, 절차적 프로그래밍에서 McCabe의 상한값 10과 자바 프로그래밍에서의 Lopez의 상한값 5에 대하여 웹 프로그래밍 구문에 이들 설정값의 적용이 가능한가?에 대한 실험으로 10 웹 사이트 프로젝트를 수집하였고 4,000여개의 ASP파일 표본이 측정되었다. 웹 어플리케이션에 대한 복잡도 빈도분포를 파악한 결과 통합된 웹 어플리케이션의 90% 이상이 복잡도 50이하의 값을 가짐으로써 한계값 50이 제안되었다. 서버, 클라이언트, HTML이 통합된 웹 어플리케이션의 구조상 HTML의 복잡도가 35~40의 값을 가지게 되는데 이는 HTML이 주로 홈 페이지나 사이트 맵을 구성하는 메뉴 형태로 되어 있어 높은 복잡도의 적합성이 설명되었다. 향후 웹 어플리케이션의 구조상 복잡도와 관련된 숨어 있는 속성은 없는지 관련성을 찾아보는 노력이 필요하다.

• Fisheries and Aquatic Sciences
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• 제24권4호
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• pp.171-179
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• 2021

To better understand the ecological functioning of the coastal ecosystem in Gamak Bay on the southern coast of Korea, seasonal changes in the density, biomass, and secondary production of the copepod community were investigated. Environmental measurements (temperature, salinity, and chlorophyll a) and copepod sampling were performed seasonally from January to December 2006. The mean density of copepods (excluding nauplii) varied from 949 to 5,999 ind · m^-3; copepod density was at its highest from March to July. The copepod community comprised 32 taxa, including Calanoida, Cyclopoida, and Harpacticoida. The predominant species were Paracalanus parvus s. l., Acartia omorii, Eurytemora pacifica, Oithona similis, A. erythraea, Centropages abdominalis, Pseudodiaptomus marinus, and Calanus sinicus. There were significant spatial and seasonal variations in copepod total biomass, which ranged from 0.33 to 43.10 mg C m^-3. Mean secondary production of the copepods in Gamak Bay, estimated as 2.05 ± 1.63 mg C m^-3 d^-1 using the Huntley and Lopez growth model, was over 2 times higher than the value given by application of the Hirst and Bunker model (1.09 ± 0.85 mg C m^-3 d^-1). The daily production rate to biomass (P/B) ratio varied between 0.08 and 0.86 d^-1 (Huntley and Lopez model), and 0.18 and 0.33 d^-1 (Hirst and Bunker model). Our results emphasize the ecological significance of using models to estimate the secondary production of copepods and provides the first report of copepod production in Gamak Bay.

• Safety and Health at Work
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• 제15권1호
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• pp.80-86
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• 2024

Background: The Work Ability Index (WAI) is an instrument that measures work ability. The wide dispersion of the WAI internationally has led to its adaptation for use in different countries. This study aimed to evaluate the psychometric properties of the Spanish version of the WAI. Methods: A methodological design was used over an opportunistic sample of 233 workers in the aeronautical industry in Spain. Reliability was evaluated through internal consistency. Factorial validity, known groups, and convergent validity were tested. Results: The Cronbach's alpha and item-total correlation indicated an adequate internal consistency. The confirmatory factor analysis, performed to evaluate the factorial validity, found adequate fit indices for a two-factor solution with a high correlation between the factors. Factor 1, "Subjectively estimated work ability and resources", was composed of 3 subscales and factor 2, "Ill-health-related", of 2 subscales. Subscales 4 and 6 had loading in both factors. Workers under 45 years of age obtained higher significant scores than older ones. Convergent validity was also evidenced since WAI was highly correlated with self-assessment of health status. Conclusions: The Spanish version of the WAI has shown evidence of reliability and validity in this study, supporting its use in individual and collective health surveillance by occupational health professionals. The factorial solution that was found has previously been reported in another international context. However, further research is needed to resolve the discrepancies detected in the role of some subscales between other national and international studies.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권2호
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• pp.118-122
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• 2005

Electro-chemo-mechanical devices or artificial muscles based on conducting polymers (CP) are presented as bilayers, CP/adhesive polymer, or as triple layers, CP/adhesive polymer/CP. Those soft and wet materials, working in aqueous solutions of a salt, mimic the composition of most organs from animals. Under electrochemical control, so working as new electrical machines, they produce continuous, reverse and elegant bending movements, mimicking those produce by animal muscles. By means of the current a perfect controls of the movement rate is attained giving soft and continuous movements. Muscles able to sense the chemical and mechanical conditions of work or muscle having tactile sense, as will be presented here, are being developed. All of them are founded on the non-stoichiometric nature of the soft and wet materials.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.72-74
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• 2003

There has been extensive interest in the development of new nanocomposites. One kind of these systems is the hybrid based on organic polymers and inorganic minerals consisting of layered silicates. Some properties like stiffness, strength, barrier properties, thermal, and oxidative stability can be improved by the presence of the filler in the polymeric matrix[1]. It is reported that, in the nylon 6/clay nanocomposites, the modulus is increased, but impact strength and elongation at break are drastically decreased. (omitted)

• ETRI Journal
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• 제30권1호
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• pp.113-128
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• 2008

Turbo codes are extensively used in current communications standards and have a promising outlook for future generations. The advantages of software defined radio, especially dynamic reconfiguration, make it very attractive in this multi-standard scenario. However, the complex and power consuming implementation of the maximum a posteriori (MAP) algorithm, employed by turbo decoders, sets hurdles to this goal. This work introduces an ASIP architecture for the MAP algorithm, based on a dual-clustered VLIW processor. It displays the good performance of application specific designs along with the versatility of processors, which makes it compliant with leading edge standards. The machine deals with multi-operand instructions in an innovative way, the fetching and assertion of data is serialized and the addressing is automatized and transparent for the programmer. The performance-area trade-off of the proposed architecture achieves a throughput of 8 cycles per symbol with very low power dissipation.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2004년도 International Conference on Digital Policy & Management
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• pp.13-24
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• 2004

Administrative procedures are the heart of the activity in each Town Council. Citizens do transactions every day and, sometimes, they do not understand what they must do or the steps to follow. We are developing a Web-based system to help citizens with this task in an easy way. The application is integrated a four year project called Albacete[Digital] that began in 2002 with the purpose of building an e-government system in Albacete, a city with over 150.000 citizens. This Administrative Information Centre is the result of the Administration study in the first year of the project and it will continue with the on-line transaction in the following years.